This document provides a learning guide on linear functions. It includes: 1) Background information on the topic, intended cycle, and instructor. 2) An example problem about two academies with different monthly payment structures for soccer lessons. Students are asked to represent the relationships mathematically and determine when payments would be equal. 3) Explanations and examples of linear functions, including completing tables to represent the payment structures and graphing the relationships. Students are asked to use this information to answer the questions from the example problem.